Harvard police arrested a man in the Science Center yesterday on charges of larceny, trespassing, and selling false railroad passes--possibly to students.

Lt. Charles A. Schwab of Harvard police said Gregory Johnson was arrested near the first-floor elevators at about 2:30 p.m. by several officers, after setting up a surveillance to nab him.

The suspect also has an outstanding arrest warrant for felony theft in Kansas, Schwab said.

Kusumarn Thammongkol '95 said yesterday she was swindled a few weeks ago by a man who fits Johnson's description.

Thammongkol said she had seen a sign on the bulletin board in front of the Science Center elevators advertising Amtrack tickets to D.C. and to New York with "no restrictions on time."

The notice, Thammongkol said, required her to leave her name and telephone number on the bulletin board and to wait to be called back.

A few days later, a man arranged for Thammongkol to meet him in front of the elevators where he sold her the tickets for $60 in cash. She latter discovered the tickets were invalid.

"He looked like a con man, I mean he really did," said Thammongkol. "I was really mad at myself when I realized, because I should have known."